The present invention relates to a fuel evaporator for heating an air-fuel mixture to promote the evaporation of fuel therein in an internal combustion engine.
Conventionally, the fuel evaporator of this type is provided with a heater element made of ceramic having a positive temperature coefficient of resistance (PTC ceramic) such as barium titanate.
The PTC ceramic does not overheat due to the self electric current control function thereof so as to be effective as a heater element of the fuel evaporator.
However, many members such as a heater element, a casing for retaining the heater element, a power supply member for supply power to the heater element, and an insulating member for fixing the casing to an air-fuel mixture passage, must be assembled in order to install the conventional fuel evaporator in the air-fuel mixture passage. And troublesome works are required for assembling them.
When the heater element which is fragile, is broken, pieces of broken element is in danger of being inspired into a combustion chamber of the engine together with an air-fuel mixture.